var toTop = document.querySelector("#toTop");
window.onscroll=function(){
	if(document.documentElement.scrollTop > 600){
		toTop.style.display = 'block'
	}else{
		toTop.style.display = 'none'
	}
}
toTop.addEventListener('click',function(){
	window.scrollTo({
		top: 0,
			behavior: 'smooth'
	})
})